Minimum Radii of Super-Earths: Constraints from Giant Impacts

Abstract

The detailed interior structure models of super-Earth planets show that there is degeneracy in the possible bulk compositions of a super-Earth at a given mass and radius, determined via radial velocity and transit measurements, respectively. In addition, the upper and lower envelopes in the mass--radius relationship, corresponding to pure ice planets and pure iron planets, respectively, are not astrophysically well motivated with regard to the physical processes involved in planet formation. Here we apply the results of numerical simulations of giant impacts to constrain the lower bound in the mass--radius diagram that could arise from collisional mantle stripping of differentiated rocky/iron planets. We provide a very conservative estimate for the minimum radius boundary for the entire mass range of large terrestrial planets. This envelope is a readily testable prediction for the population of planets to be discovered by the Kepler mission.

8 pages, 4 figures, Accepted for publication in ApJ Letters

References in corpus (11)

• Planetary Radii across Five Orders of Magnitude in Mass and Stellar Insolation: Application to Transits
• Towards a Deterministic Model of Planetary Formation I: a Desert in the Mass and Semi Major Axis Distributions of Extra Solar Planets
• A super-Earth transiting a nearby low-mass star
• Transiting exoplanets from the CoRoT space mission VIII. CoRoT-7b: the first Super-Earth with measured radius
• Internal Structure of Massive Terrestrial Planets
• Extrasolar planet population synthesis I: Method, formation tracks and mass-distance distribution
• Detailed Models of super-Earths: How well can we infer bulk properties?
• Ocean Planet or Thick Atmosphere: On the Mass-Radius Relationship for Solid Exoplanets with Massive Atmospheres
• Extrasolar planet population synthesis II: Statistical comparison with observation
• A Study of the Accuracy of Mass-Radius Relationships for Silicate-Rich and Ice-Rich Planets up to 100 Earth Masses
• Collisional Stripping and Disruption of Super-Earths

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